Why We Measure

A few weeks ago I found myself mentioned in a rant by CNET's Steve Guttenberg. Steve thinks it's dumb for anyone but a product designer to measure the performance of audio gear. He mentioned me because I take the opposing view.

Steve made some good points in his blog, citing instances in which trusting too much in measurements has led the audio industry astray. But IMHO, he overlooked the many valid reasons for reviewers to measure audio gear as well as listen to it. I guess the job of filling in the missing half of his article falls to me, so here goes. . .

I've spent 22 years covering the audio industry, as a senior editor at Video magazine, editor-in-chief of Home Theater and Home Entertainment, and contributing technical editor of Sound + Vision. I've known countless reviewers, from some of the guys who started the whole thing back in the 1960s to writers in their 20s and 30s who've been at it for just a year or two. I've hired many dozens of them, edited their work, and checked out the products they've reviewed on my own. And after all that experience, there's one thing I've learned:

I don't trust them. Not 100 percent, anyway.

Even the best and brightest of reviewers can overlook serious flaws in a product. Any of us can fall in love with a piece of gear for the wrong reasons. Maybe the device does one thing so spectacularly well, we inadvertently ignore a problem that a user with different priorities would find in minutes. And as much as every reviewer tries to be unbiased, we all expect certain brands to be good and others to suck. We're human. We can be prejudiced. We can be swayed.

My measurement gear, on the other hand, cannot be swayed. A manufacturer can't buy lunch for my Clio FW and Audio Precision analyzers. Test gear doesn't care how much a product costs or how cool it looks or how hot the public-relations person is. It just tells you the facts.

Here's an exercise that illustrates my point: Look in any high-end audio magazine and you'll see rave reviews of esoteric, expensive speakers. Go hear a few of those speakers at a dealer or a hi-fi show. I guarantee you will hear one or two that blow you away with sound quality you didn't think possible. I also guarantee you'll hear one or two that leave you questioning the reviewer's sanity and/or integrity.

And I absolutely, positively guarantee you that the speakers you don't like don't measure well.

In fact, of all the countless speakers Steve reviewed for me when I was an editor, there were only a couple that he loved that I didn't like. The frequency response measurements of those speakers were horrible.

Those speakers' unusual properties clearly seduced Steve, and it's important that we hear that side of the story. But it's equally important to be aware of technical shortcomings that a subjective reviewer might miss. These speakers' flaws apparently didn't cause problems in Steve's listening room, or with the music he used to test the speakers. Or maybe his taste in sound allows him to tolerate these speakers' particular problems. But your tastes in sound and music likely differ from Steve's, and the acoustics of your listening room definitely differ from his.

Those of us who measure audio gear as well as listen to it don't blindly trust our meters. We trust science. Many years ago, researchers at Canada's National Research Council in Ottawa decided to find out if one could use measurements to predict which speakers listeners would like. They found out that indeed, you could. In blind tests, listeners tend to prefer speakers with a frequency response that's flat on-axis and smooth off-axis, with no major peaks and dips until you get way off-axis.

Such speakers also tend to perform more consistently in a variety of acoustic environments, i.e., they're not as affected by room acoustics. This isn't opinion. It's scientific fact based on countless listening tests, all of which were far more meticulous than those that reviewers conduct in their homes.

I challenge you: Name a speaker that delivers flat on-axis response and smooth off-axis response that doesn't sound good. I've reviewed and measured way more than a thousand speakers, and I can't think of a single example.

Measurements also allow the reviewer to gauge a product's suitability for other listeners' tastes and listening rooms. In a recent review, I compared the Hsu Research VTF-15H subwoofer to the SVS PB12-NSD. Even in my fairly large, 2,950-cubic-foot listening room, playing DVDs and Blu-rays at full Dolby reference level, I could barely tell the difference between these two subs. But my measurements showed a clear advantage for the larger, more expensive VTF-15H in the bottom octave of bass (20-31.5 Hz). If you have a larger room or want to play at even higher levels, or if you really love super-deep bass, my subjective evaluation would have told you absolutely nothing about these subs. My measurements, however, tell you everything you need to know.

None of this means that the speaker that measures better always sounds better. About six years ago, I tested two speakers with similar form factors: the Earthquake Sound Platine Noirée and a tower speaker from Definitive Technology's Mythos line. (The model number escapes me.) The Mythos measured great and sounded great; they were the product of meticulous, by-the-book engineering. The Platine Noirée measured badly, with major peaks and dips in the frequency response. It was obvious when I disassembled the Platine Noirée that it wasn't the product of a careful engineering effort. Yet I preferred its sound.

This could have been for any number of reasons. Maybe my room's acoustics suited the Platine Noirée better. Maybe its sound was particularly appropriate for my taste or the music I listen to. I don't know, but I gave the readers both my subjective impression and the measurements, so they'd know the pros and cons and they'd be sure to give the Platine Noirée a good, long listen before purchasing it.

I'm not saying reviewers should ignore their ears. Ultimately, any audio product must be judged on whether or not the sound arriving at your ears pleases you. But a single reviewer's ears cannot provide a complete assessment of the performance of an audio product. The only way to produce audio equipment reviews that are useful for any and every reader is to combine the art and the science, the subjective and the objective, the ears and the meters.